Tricksters stole £300 from an elderly woman from a Downham car park.
A bankcard was taken from the victim, who is in her 80s, as she gave another woman directions in the Tesco car park on Wednesday at 1pm.
The conwoman is described as having olive skin, spoke with a foreign accent and was approximately 5ft 5in and in her early 30s. She was accompanied by a man who was described as being in his 40s or 50s with balding grey hair and of stocky build with missing teeth.
Police have put out a warning and appeal for help.